Hi, the top drawer on my DD603 stopped working at the start of a wash cycle (there's a caustic smell to the water sitting in the base).

The bottom drawer works fine, but the top drawer doesn't register any power. I've swapped out the control boards (which are both pretty new anyway) and it still doesn't work. I also swapped over the LCD modules - still not showing any power on the top drawer.

Looking at the wiring diagram for this model, I can see that there are two live wires that come into the control board - I've tested these and they are both showing the correct voltage, so there's power going into the control board.

The wiring diagram also shows the these two live wires continue over the heater plate, and I notice that there's a thermal fuse in there.

I'm guessing that the thermal fuse has failed - would this be a reasonable assumption?

If so:
- how do I remove the thermal fuse?
- is it a replaceable part? (i.e. can I purchase it from F&P - I've read that it is simply solder)
- if a thermal fuse has gone, does this mean that there is another issue with the heating plate, or is this a part that regularly goes?

When you come to replace heater plate have a look at my post "fisher & paykel DD603 heater plate fuse burnt out." ( not sure how to give link to this post..) includes a comment from someone else as well... I used new seals and they are a bit tight.. but certainly have not leaked!..You will need to follow the manual but it is not that hard.

remember: if running diagnostics.. dont test element without water in the tub.. . it may overheat..

Didn't see your post, have just pulled it apart to fix it - damn I love this dishwasher, it's so easy to fix.

Anyway, popped out the heater plate, and sure enough the thermal fuse was a bit cruddy, and actually fell off quite easily - just looks old and oxidized, no discernable issues with shorts etc. On consultation with my dad (as usual), we worked out what type of wire and how many strands to replace it with. Initially went one strand less than what we worked out to be on the safe side (i.e. would rather it burnt out before a major melt down). Soldered it in, cleaned up all the mating surfaces for the seals, and put it all back together again.

Doing a test wash now, and no leaks, and water has heated sucessfully, so all looking good. Will try and find the thread you mention to make sure I haven't missed anything, but all looking good at the moment.

Yes fair point - next will try and source some suitable temp sensitive fuse wire to fix it up properly. I hate buying new when there's a chance of fixing things. At the moment it's electrically safe, and we don't run it when we are out of the house ever.

I had same idea when mine failed but decided against it.. I think your fuse looked cruddy because it got overheated.... if the heater plate gets overheated again and there is no thermal fuse... ?? you might smell the plastic in the tub geting a bit hot.. or worse, .

If you can source thermal fuse that would be great..

I have three of these machines in family and friends and have only one of these fail in five years, and that was because of a fault in the controller board which then kept the heater on..

I've previously replaced the controller boards (on both drawers), so maybe that is what caused it - hopefully won't be a problem now. Anyway, I'll try and source some thermal fuse wire that can be soldered, otherwise will fork out for a new heating plate. It's working great at the moment, and the fire extinguisher is on standby.....

Hi, I'm looking at a fix for the thermal fuse now, and the thermal fuse is pretty old school now apparently - I've been told that a Microtemp thermal fuse is now the way to go. I can get one of these really cheap of ebay, and they will do temperatures up to 275 degrees Celcius, which is right in the correct range, and it should solder right onto the heater plate no probs.

The cost is all of about $US4, + postage, which beats buying a new heating plate.

Does anyone have any thoughts on using a Microtemp thermal fuse? i.e. any specific issues which will prevent me from using this?

I don't think amps will be a problem, generally in this temp range they can support about 10 amps - problem I have now is that I can't find the 275 degree items anymore - can't remember where I saw them.